Well it would help to know the weight of the truck first.I have installed a few sets SS springs on my car and it always seems that I go too light.There are some good Ford stick racers over on www.umtrnorth.com that could critique your setup and guide you as well.
Gus

64 Plymouth Savoy
493 Indy EZ's by Nick at Compu-Flow
5-Speed Richmond faceplate Liberty box
Dana 60